Just a little update...
If you plan on doing this modification be aware you are using your boat in ways that were never intended. I noticed the lower pylon mount failing after probably a dozen or so ATB's with 3-4 skiers in tow. I would strongly suggest you modify your lower pylon mount with something stronger than the OEM version, it can't handle the side loads generated. I fabricated a close replica out of some steel, instead of aluminum.